Image output devices include all of devices that receive and output broadcasting or record and reproduce videos and devices that record and reproduce audios. Examples of the image output device include televisions, smart TVs, computer monitors, all-in-one or integral PCs in which a monitor and a main body are coupled to each other, laptop computers, projectors, tablets, mobile terminals and the like.
As it becomes multifunctional, an image output device can be allowed to reproduce broadcast, music or video files, capture still images or moving images, play games, receive broadcast and the like, so as to be implemented as an integrated multimedia player. In addition, an image output device is currently realized as a smart device (e.g., smart television). Accordingly, the image output device executes an Internet and the like, and also operates in cooperation with a mobile terminal, a computer or a server.
Meanwhile, in recent years, cases in which a user outputs screen information using a plurality of image output devices are increasing, and accordingly, function and method for adjusting image qualities of the plurality of image output devices are being continuously developed.
In recent years, with the increase in the cases in which the user outputs the screen information using the plurality of image output devices, a method of controlling the plurality of image output devices using a mobile terminal may be considered.